Add support for original_dst for windows (#529)

Author: keithmattix

src/socket.rs

@@ -2225,6 +2225,48 @@ impl Socket {
             )
         }
     }
+
+    /// Get the value for the `SO_ORIGINAL_DST` option on this socket.
+    #[cfg(all(
+        feature = "all",
+        any(
+            target_os = "android",
+            target_os = "fuchsia",
+            target_os = "linux",
+            target_os = "windows",
+        )
+    ))]
+    #[cfg_attr(
+        docsrs,
+        doc(cfg(all(
+            feature = "all",
+            any(
+                target_os = "android",
+                target_os = "fuchsia",
+                target_os = "linux",
+                target_os = "windows",
+            )
+        )))
+    )]
+    pub fn original_dst(&self) -> io::Result<SockAddr> {
+        sys::original_dst(self.as_raw())
+    }
+
+    /// Get the value for the `IP6T_SO_ORIGINAL_DST` option on this socket.
+    #[cfg(all(
+        feature = "all",
+        any(target_os = "android", target_os = "linux", target_os = "windows")
+    ))]
+    #[cfg_attr(
+        docsrs,
+        doc(cfg(all(
+            feature = "all",
+            any(target_os = "android", target_os = "linux", target_os = "windows")
+        )))
+    )]
+    pub fn original_dst_ipv6(&self) -> io::Result<SockAddr> {
+        sys::original_dst_ipv6(self.as_raw())
+    }
 }
 
 impl Read for Socket {

src/sys/unix.rs

@@ -1406,6 +1406,47 @@ pub(crate) const fn to_mreqn(
     }
 }
 
+#[cfg(all(
+    feature = "all",
+    any(target_os = "android", target_os = "fuchsia", target_os = "linux")
+))]
+pub(crate) fn original_dst(fd: Socket) -> io::Result<SockAddr> {
+    // Safety: `getsockopt` initialises the `SockAddr` for us.
+    unsafe {
+        SockAddr::try_init(|storage, len| {
+            syscall!(getsockopt(
+                fd,
+                libc::SOL_IP,
+                libc::SO_ORIGINAL_DST,
+                storage.cast(),
+                len
+            ))
+        })
+    }
+    .map(|(_, addr)| addr)
+}
+
+/// Get the value for the `IP6T_SO_ORIGINAL_DST` option on this socket.
+///
+/// This value contains the original destination IPv6 address of the connection
+/// redirected using `ip6tables` `REDIRECT` or `TPROXY`.
+#[cfg(all(feature = "all", any(target_os = "android", target_os = "linux")))]
+pub(crate) fn original_dst_ipv6(fd: Socket) -> io::Result<SockAddr> {
+    // Safety: `getsockopt` initialises the `SockAddr` for us.
+    unsafe {
+        SockAddr::try_init(|storage, len| {
+            syscall!(getsockopt(
+                fd,
+                libc::SOL_IPV6,
+                libc::IP6T_SO_ORIGINAL_DST,
+                storage.cast(),
+                len
+            ))
+        })
+    }
+    .map(|(_, addr)| addr)
+}
+
 /// Unix only API.
 impl crate::Socket {
     /// Accept a new incoming connection from this listener.
@@ -2402,62 +2443,6 @@ impl crate::Socket {
         }
     }
 
-    /// Get the value for the `SO_ORIGINAL_DST` option on this socket.
-    ///
-    /// This value contains the original destination IPv4 address of the connection
-    /// redirected using `iptables` `REDIRECT` or `TPROXY`.
-    #[cfg(all(
-        feature = "all",
-        any(target_os = "android", target_os = "fuchsia", target_os = "linux")
-    ))]
-    #[cfg_attr(
-        docsrs,
-        doc(cfg(all(
-            feature = "all",
-            any(target_os = "android", target_os = "fuchsia", target_os = "linux")
-        )))
-    )]
-    pub fn original_dst(&self) -> io::Result<SockAddr> {
-        // Safety: `getsockopt` initialises the `SockAddr` for us.
-        unsafe {
-            SockAddr::try_init(|storage, len| {
-                syscall!(getsockopt(
-                    self.as_raw(),
-                    libc::SOL_IP,
-                    libc::SO_ORIGINAL_DST,
-                    storage.cast(),
-                    len
-                ))
-            })
-        }
-        .map(|(_, addr)| addr)
-    }
-
-    /// Get the value for the `IP6T_SO_ORIGINAL_DST` option on this socket.
-    ///
-    /// This value contains the original destination IPv6 address of the connection
-    /// redirected using `ip6tables` `REDIRECT` or `TPROXY`.
-    #[cfg(all(feature = "all", any(target_os = "android", target_os = "linux")))]
-    #[cfg_attr(
-        docsrs,
-        doc(cfg(all(feature = "all", any(target_os = "android", target_os = "linux"))))
-    )]
-    pub fn original_dst_ipv6(&self) -> io::Result<SockAddr> {
-        // Safety: `getsockopt` initialises the `SockAddr` for us.
-        unsafe {
-            SockAddr::try_init(|storage, len| {
-                syscall!(getsockopt(
-                    self.as_raw(),
-                    libc::SOL_IPV6,
-                    libc::IP6T_SO_ORIGINAL_DST,
-                    storage.cast(),
-                    len
-                ))
-            })
-        }
-        .map(|(_, addr)| addr)
-    }
-
     /// Copies data between a `file` and this socket using the `sendfile(2)`
     /// system call. Because this copying is done within the kernel,
     /// `sendfile()` is more efficient than the combination of `read(2)` and

src/sys/windows.rs

@@ -20,14 +20,16 @@ use std::time::{Duration, Instant};
 use std::{process, ptr, slice};
 
 use windows_sys::Win32::Foundation::{SetHandleInformation, HANDLE, HANDLE_FLAG_INHERIT};
-#[cfg(feature = "all")]
-use windows_sys::Win32::Networking::WinSock::SO_PROTOCOL_INFOW;
 use windows_sys::Win32::Networking::WinSock::{
     self, tcp_keepalive, FIONBIO, IN6_ADDR, IN6_ADDR_0, INVALID_SOCKET, IN_ADDR, IN_ADDR_0,
     POLLERR, POLLHUP, POLLRDNORM, POLLWRNORM, SD_BOTH, SD_RECEIVE, SD_SEND, SIO_KEEPALIVE_VALS,
     SOCKET_ERROR, WSABUF, WSAEMSGSIZE, WSAESHUTDOWN, WSAPOLLFD, WSAPROTOCOL_INFOW,
     WSA_FLAG_NO_HANDLE_INHERIT, WSA_FLAG_OVERLAPPED,
 };
+#[cfg(feature = "all")]
+use windows_sys::Win32::Networking::WinSock::{
+    IP6T_SO_ORIGINAL_DST, SOL_IP, SO_ORIGINAL_DST, SO_PROTOCOL_INFOW,
+};
 use windows_sys::Win32::System::Threading::INFINITE;
 
 use crate::{MsgHdr, RecvFlags, SockAddr, TcpKeepalive, Type};
@@ -857,6 +859,46 @@ pub(crate) fn to_mreqn(
     }
 }
 
+#[cfg(feature = "all")]
+pub(crate) fn original_dst(socket: Socket) -> io::Result<SockAddr> {
+    unsafe {
+        SockAddr::try_init(|storage, len| {
+            syscall!(
+                getsockopt(
+                    socket,
+                    SOL_IP as i32,
+                    SO_ORIGINAL_DST as i32,
+                    storage.cast(),
+                    len,
+                ),
+                PartialEq::eq,
+                SOCKET_ERROR
+            )
+        })
+    }
+    .map(|(_, addr)| addr)
+}
+
+#[cfg(feature = "all")]
+pub(crate) fn original_dst_ipv6(socket: Socket) -> io::Result<SockAddr> {
+    unsafe {
+        SockAddr::try_init(|storage, len| {
+            syscall!(
+                getsockopt(
+                    socket,
+                    SOL_IP as i32,
+                    IP6T_SO_ORIGINAL_DST as i32,
+                    storage.cast(),
+                    len,
+                ),
+                PartialEq::eq,
+                SOCKET_ERROR
+            )
+        })
+    }
+    .map(|(_, addr)| addr)
+}
+
 #[allow(unsafe_op_in_unsafe_fn)]
 pub(crate) fn unix_sockaddr(path: &Path) -> io::Result<SockAddr> {
     // SAFETY: a `sockaddr_storage` of all zeros is valid.

tests/socket.rs

@@ -1600,36 +1600,57 @@ fn header_included_ipv6() {
 #[test]
 #[cfg(all(
     feature = "all",
-    any(target_os = "android", target_os = "fuchsia", target_os = "linux")
+    any(
+        target_os = "android",
+        target_os = "fuchsia",
+        target_os = "linux",
+        target_os = "windows"
+    )
 ))]
 fn original_dst() {
     let socket = Socket::new(Domain::IPV4, Type::STREAM, None).unwrap();
+    #[cfg(not(target_os = "windows"))]
+    let expected = Some(libc::ENOENT);
+    #[cfg(target_os = "windows")]
+    let expected = Some(windows_sys::Win32::Networking::WinSock::WSAEINVAL);
+
     match socket.original_dst() {
         Ok(_) => panic!("original_dst on non-redirected socket should fail"),
-        Err(err) => assert_eq!(err.raw_os_error(), Some(libc::ENOENT)),
+        Err(err) => assert_eq!(err.raw_os_error(), expected),
     }
 
     let socket = Socket::new(Domain::IPV6, Type::STREAM, None).unwrap();
     match socket.original_dst() {
         Ok(_) => panic!("original_dst on non-redirected socket should fail"),
-        Err(err) => assert_eq!(err.raw_os_error(), Some(libc::ENOENT)),
+        Err(err) => assert_eq!(err.raw_os_error(), expected),
     }
 }
 
 #[test]
-#[cfg(all(feature = "all", any(target_os = "android", target_os = "linux")))]
+#[cfg(all(
+    feature = "all",
+    any(target_os = "android", target_os = "fuchsia", target_os = "linux")
+))]
 fn original_dst_ipv6() {
     let socket = Socket::new(Domain::IPV6, Type::STREAM, None).unwrap();
+    #[cfg(not(target_os = "windows"))]
+    let expected = Some(libc::ENOENT);
+    #[cfg(target_os = "windows")]
+    let expected = Some(windows_sys::Win32::Networking::WinSock::WSAEINVAL);
+    #[cfg(not(target_os = "windows"))]
+    let expected_v4 = Some(libc::EOPNOTSUPP);
+    #[cfg(target_os = "windows")]
+    let expected_v4 = Some(windows_sys::Win32::Networking::WinSock::WSAEINVAL);
     match socket.original_dst_ipv6() {
         Ok(_) => panic!("original_dst_ipv6 on non-redirected socket should fail"),
-        Err(err) => assert_eq!(err.raw_os_error(), Some(libc::ENOENT)),
+        Err(err) => assert_eq!(err.raw_os_error(), expected),
     }
 
     // Not supported on IPv4 socket.
     let socket = Socket::new(Domain::IPV4, Type::STREAM, None).unwrap();
     match socket.original_dst_ipv6() {
         Ok(_) => panic!("original_dst_ipv6 on non-redirected socket should fail"),
-        Err(err) => assert_eq!(err.raw_os_error(), Some(libc::EOPNOTSUPP)),
+        Err(err) => assert_eq!(err.raw_os_error(), expected_v4),
     }
 }